﻿/* ==============================================================================
*
*   Copyright (c) 2010, Pierre Favier
*   All rights reserved.
*
*   NTasking is free software: you can redistribute it and/or modify it
*   under the terms of the GNU General Public License as published by the
*   Free Software Foundation.
*
*   Redistribution and use in source and binary forms, with or without
*   modification, are permitted provided that the following conditions
*   are met:
*
*   -   Redistributions of source code must retain the above copyright notice,
*       this list of conditions and the following disclaimer.
*
*   -   Redistributions in binary form must reproduce the above
*       copyright notice, this list of conditions and the following
*       disclaimer in the documentation and/or other materials
*       provided with the distribution.
*
*   THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
*   WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
*   OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
*   DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS
*   BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
*   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
*   TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
*   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
*   ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
*   TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
*   THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
*   SUCH DAMAGE.
*
* ============================================================================== */

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;

namespace NTasking.Internals
{

    /// <summary>
    /// Provide tracing facilities for the Ntasking library when the TASKING_DEBUG symbol is defined
    /// </summary>
    internal static class Tracer
    {

        private static readonly object _globalLock = new object();

        private static readonly Dictionary<ITask, int> _allTasks = new Dictionary<ITask, int>();


        [Conditional("TASKING_DEBUG")]
        internal static void Trace(string message)
        {
            StackTrace trace = new StackTrace();
            int frame = 1;

            while (true)
            {
                Type declaringType = trace.GetFrame(frame).GetMethod().DeclaringType;

                //if (declaringType != typeof(ThreadWrapper))
                //    return;

                //frame += 1;

                //if (trace.GetFrame(frame).GetMethod().DeclaringType == typeof(CodeWrapper))
                //    frame += 2;

                //break;

                if (declaringType != typeof(ThreadWrapper) && declaringType != typeof(ManagedLock) && declaringType != typeof(CodeWrapper))
                    break;

                frame += 1;
            }

            System.Reflection.MethodBase method = trace.GetFrame(frame).GetMethod();

            Console.WriteLine(string.Format("[{0}]\t{3}\t{1}.{2}",
                              Task.CurrentTask,
                              method.DeclaringType.Name,
                              method.Name,
                              message));
        }


        [Conditional("TASKING_DEBUG")]
        internal static void StartOperation()
        {
            ITask task = Task.CurrentTask;

            lock (_globalLock)
            {
                int count;
                _allTasks.TryGetValue(task, out count);
                _allTasks[task] = count + 1;
            }
        }


        [Conditional("TASKING_DEBUG")]
        internal static void EndOperation()
        {
            ITask task = Task.CurrentTask;

            lock (_globalLock)
            {
                if (!_allTasks.ContainsKey(task))
                    return;

                int count = _allTasks[task];

                if (count > 1)
                    _allTasks[task] = count - 1;
                else
                    _allTasks.Remove(task);
            }
        }


        internal static KeyValuePair<ITask, string>[] AllTasksState
        {
            get
            {
                return (from task in _allTasks.Keys
                        let itask = (ITaskInternal) task
                        select new KeyValuePair<ITask, string>(task, itask.StateString())).ToArray();
            }
        }
    }

}
